1. Field of the Invention
The present invention relates to an air conditioning apparatus which can perform a dehumidifying operation, to thereby removing water from the air in a room.
2. Description of the Related Art
Air conditioners are known which have two indoor heat exchangers located in a room and in which these heat exchangers can be used as evaporators to cool the room, and also as an evaporator and a condenser, respectively, to dehumidifying the room. In the dehumidifying operation, one of the indoor heat exchangers is used as an evaporator to cool the room, whereas the other indoor heat exchanger is used as a condenser to reheat the air thus cooled and hence dehumidified, to room temperature. The air dehumidified and reheated is supplied into the room.
Among these air conditioners are two types. In the first type, both the indoor temperature and the indoor humidity are measured during the dehumidifying operation, and the frequency of driving the compressor is determined in accordance with the position the indoor temperature and the indoor humidity relationship assumes in a matrix chart. In the second type, the rotational speed of the outdoor fan is controlled in accordance with the indoor temperature, to thereby change the sensible heat of the outdoor heat exchanger to adjust the temperature of the air which is being supplied into the room.
It is desirable that an air conditioner control the temperature and humidity in a room in accordance with various load conditions. Among these conditions are: the structure of the building including the room; the climate of the region where the building is located; and the bodily sensation of the persons staying in the room.
An air conditioner which controls the indoor temperature and the indoor humidity is disclosed in Jpn. Pat. Appln. KOKAI Publication No. 3-13751. This air conditioner has sensors and a microcomputer. The sensors detects the indoor conditions. The microcomputer performs fuzzy inference based on the indoor conditions detected, thereby determining an optimal temperature to which air should be heated before supplied into the room and also an optimal amount in which the heated air should be supplied into the room. The outdoor heat exchanger heats air to the optimal temperature, and the air thus heated is supplied into the room in the optimal amount. The indoor temperature is thereby maintained at a preset value desirable for the people staying in the room.
Another air conditioner which controls the indoor temperature and the indoor humidity is disclosed in Jpn. Pat. Appln. KOKAI Publication No. 1-276319. In this air conditioner, the indoor temperature and the changes thereof are detected and used to control the capacity of the compressor.
The air conditioners disclosed in these publications control the indoor temperature only. They cannot control the indoor humidity.